RYE-FLOUR

Abstract: The invention concerns rye-flours with either less than 7 wt% protein or with more than 12 wt% protein. These flours can be obtained as the result of classification of rye-flour with 7-12 wt% protein.

Description: Rye-f lour Rye-containing bakery products, such as Rye-breads are well known. Those products are made from doughs, that contain Rye-flour. So far problems occurred during the production and handling of doughs, that had a too high content of Rye- flour. In particular doughs, wherein more that 50% of the flour consists of Rye-flour give problems because they are too sticky. Therefore, those doughs could not be produced in a continuous process, because of problems with the machinability of the doughs. We have studied above problem in order to find a solution. This study has resulted in our invention. According to this invention we have found a new Rye-flour, that can be used in high levels (even up to 100% on flour- component) in Rye-containing doughs, while the doughs are not sticky and can be produced in a continuous way. Essential for our dough-composition is, that at least a considerable amount of a Rye-flour with a protein-content, below that of ordinary Rye-flour is present as part of the flour-component. Although US 3,077,408 discloses airclassification from cereal flours, such as wheat, barley, corn, durum, rice and also rye, wherein it is revealed that the fines are enriched in proteins and that the coarse has a decreased protein content, nothing is disclosed about the problem of the stickiness of a dough, based on rye-flour and the problems resulting therefrom in a continuous^process, because of the machinability of the dough. In example 7 it is only stated that the baking quality of a rye-flour is improved when a small amount of protein-enriched fines are removed. From the table in column 16, wherein amylograph peak Bu-values of the parent stock and of the fine- and the coarse-fraction are mentioned, it can be concluded that the coarse fraction and the parent stock have about the same -amylase activity. Therefore, it was not recognized in this prior art and thus it cannot be derived from the above US patent what the impact will be of the application of a coarse rye flour fraction in a dough based on rye-flour, in particular with respect of the stickiness of the dough and its effects in a continuous, fully-machinable process. Therefore, our invention concerns in the first place a new Rye-flour. This Rye-flour has a protein content of less than 7 wt%, preferably less than 5 wt%, while this flour simultaneously has a reduced dietary fibre content, compared with ordinary Rye-flour, while the particle size distribution of this Rye-flour is such that at least 20 wt% of the particles have a size above 65 μ and more than 94 wt% of the particles have a size of less than 130 μm. The dietary fibre content (as measured according to the method of L. Prosky, published in Journal of the Ass. of Off. Anal. Chemists, vol. 67, pages 1044-1052, 1984) of this Rye-flour is reduced, preferably with at least 10%, compared with ordinary (natural) Rye-flour. Simultaneously, the -amylase activity of this Rye-flour is also reduced, preferably with at least 10%, compared wit ordinary (natural) Rye-flour. The α-amylase activity can measured using a Brabender Amylograph, and is expressed in Brabender Units (= B.U.) . The lower this value, the higher the α-amylase activity. Although the new Rye-flour as defined above can be used as such as the flour-component of a Rye-bread dough, it is preferred to use a blend of an ordinary flour and our new Rye-flour. Therefore, our invention also concerns flour blends, suitable for the production of Rye-containing products, wherein ordinary flour is blended with Rye-flour, according to the invention, so that the weight ratio ordinary flour: Rye-flour ranges from (95-5) : (5-95) . The ordinary flour, used in those blends can be any flour, examples are flours derived from: wheat, oat, barley, corn, rice, sorghum, but also cereal like small grain flours, such as buck-wheat, quinoa or amaranth can be applied. It is of course also possible to blend our new Rye-flour with ordinary Rye-flour or with whole meal flour. Application of our new Rye-flour or our new blends in doughs for bakery products leads to new doughs, that are also part of our invention. Therefore, our invention also concerns dough for bakery products, comprising the usual ingredients such as flour, salt and water, and optionally yeast, sour inoculum or leavening agents or other typical ingredients such as fats, sugar, eggs, gluten or other bread-improvers, wherein the flour applied is the flour defined above or the blend defined above. Depending pn the water content of the dough, doughs are obtained, which are suitable for Rye-containing bread or for Knacke-brot. So, our invention also concerns dough for Rye-containing bread, comprising the above dough, wherein the water content of the dough is 45-60 wt% (on dough) and dough for Knacke-brot, comprising the above dough, wherein the water content of the dough is 60-70 wt%, while yeast or leavening agent is absent. The novel Rye-flour and the blends as defined above can also be used for the production of sour doughs. So, fermented sour doughs, comprising at least flour, water and a sour inoculum, wherein the flour, at least partly consists of the Rye-flour according to the invention or the blend according to the invention are also part of the invention. A preference, however, exists for fermented sour doughs with a limited water level (e.g. as disclosed in our co- pending application EP 92202055.7) . Therefore, fermented sour dough, comprising the above dough, wherein a sour inoculum is applied, while the water content of the dough is at least 25 wt%, preferably 25-32 wt% and fermented sour dough, wherein this fermented sour dough is mixed with enough of a pre-dried flour with a water content of less than 5 wt%, so that the water content of the mixture is 20- 25 wt%, are also part of the invention. Another aspect of our invention is laid in the fact that the use of our novel Rye-flours enables us to perform a continuous process for the production of Rye-containing products. Therefore, our invention also concerns a process for the production of baked Rye-containing products, wherein a dough is produced with the composition according to the invention in a continuous process, the dough is divided, moulded, fermented (if necessary) and baked. The fermentation is optional, as Knacke-brot is produced without the presence of yeast or leavening agent. The products, obtained after baking of our doughs are also part of the invention. The novel Rye-flours, disclosed above can be obtained as the coarse-fraction of an air classification process, performed on a milled, ordinary Rye-flour. Therefore, part of the invention is also a process for the air classification of a flour, wherein a Rye-flour with 7-12 wt% proteins is milled, so that the milled flour has a particle size distribution such that at least 98% has a size below 130 μm and at least 65 wt% has a size below 32 μm, the milled Rye-flour is subjected to air classification, applying a cut-point of 20-30 and an appropriate air speed, while separating a fine, protein- enriched Rye-flour with more than 12 wt% proteins having a particle size distribution such that at least 95 wt% has a particle size below 64 μm, while its α-amylase activity is increased with at least 10% compared with the starting Rye- flour in a yield of 20-40 wt% and a coarse, protein reduced Rye-flour with a protein content of less than 7 wt% having a particle size distribution such that at least 20 wt% has a size above 65 μm and more than 94 wt% has a size of less than 130 μm in a yield of 80-60 wt%. As a result of this process, a coarse, protein reduced fraction is obtained, which is the Rye-flour described above. The fine, protein- enriched Rye-flour that is also obtained, as a result of the air classification is also novel. Therefore, our invention also concerns with Rye-flour, wherein the Rye- flour has a protein content of more than 12 wt%, preferably more than 13 wt%, more preferably more than 15 wt%, which flour simultaneously has an increased dietary fibre content compared with ordinary Rye-flour. The particle size distribution of this Rye-flour is typically such that at least 95 wt% has a particle size below 64 μm. The dietary fibre content of this Rye-flour is increased, typically with at least 10% compared with ordinary Rye- flour. Simultaneously, the α-amylase activity is also increased, typically with at least 10% (based on BU- measurements) . This protein-enriched Rye-flour can also be applied as a blend with other flours. So, our invention also concerns flour blends, suitable for the production of wheat and/or Rye-containing products, wherein ordinary flour is blended with the protein-enriched Rye-flour so that the weight ratio ordinary flour: Rye-flour ranges from (0.1-99.9) : (99.9-0.1) ; preferably from (5-95) : (95:5) . Doughs for bakery products, comprising the usual ingredients such as flour, water, salt, yeast or sour inoculum or leavening agents and optionally typical ingredients such as: fats, sugar, eggs, gluten or other bread-improvers, wherein the flour applied is the above Rye-flour or flour-blend are also part of our new invention. The novel, protein-enriched Rye-flour can be used for the production of baked wheat and/or Rye-containing products, in particular bread and rolls. A very suitable blend for this application comprises (99-90) wt% of ordinary flour and (1-10) wt% of the protein-enriched Rye-flour fraction of our invention. Incorporation of these Rye-flours leads to products with improved taste, freshness, texture and flavour, compared with ordinary French bread. Examples I. Air classification of Rye-flour The air classification was carried out using an Alpine (Augsburg) pilot plant air-classifier, provided with a Turboplex fine separator 50 ATP. The starting material was remilled rye flour according to table 1. Dosage: 9.7 kg/hr. Classifying wheel velocity: 11,000 RP . A cut point of 25 was applied. A fine fraction was obtained in a yield of 20.1 wt% and a coarse fraction in a yield of 79.9 wt%. The properties of the fine and the coarse fractions are given in tables II and III. TABLE I Remilled Rye-flour ash content 0.97 % protein content 9.3 % dietary fibre content 8.5 % amylogram max. viscosity 510 BU particle size distribution 98.6% below 128 μm 68.6% below 32 μm TABLE II Air-classified coarse fraction ash content 0.92 % protein content 4.85 % (as: N x 5.8) dietary fibre content 8.0 % amylogram max. viscosity 744 BU particle size distribution 82% below 65 μm 98.5% below 130 μm TABLE III Air-classified fine fraction ash content 1.17 % protein content 13.2 % (as: N x 5.8) dietary fibre content 9.5 % amylogram max. viscosity 453 BU particle size distribution 99% below 64 μm II Preparation of Rve-containinq rolls II.1 Recipe 3350 g Rye-flour coarse fraction of example I 435 g dry gluten 369 g dried sour dough 330 g coarsly ground malt grains (Rye) 215 g whole meal Rye-flour 187 g bread improver 114 g salt 180 g yeast 3195 g water II.2 The dough was prepared in a continuous process, applying a spiral mixer under the following conditions: slow speed 6 mm higher speed 1 min dough temperature 29. 2 °C dough resting time 15 min The dough was divided and moulded, so that dough pieces of 70 gram were obtained. The dough pieces were pre-fermented during 12 min and proofed during 60 min. The fermented dough pieces were baked in a Stikken- oven 5 min at 250°C 12 min at 200°C 3 min at 230°C The specific volume of the Rye-rolls was 5.6 ml/g. The dough did not show any stickiness. II.3 The dough stickiness was measured (Chen-Hoseney fixture) by adapting the optimal water absorption and holding time of the plunger in resp. +5% water and a holding time of 0.5 sec. Two samples were tested. The results are shown below. III Preparation of French bread III.2 The dough was prepared, using a Diosna spiral mixer slow speed 7 min higher speed 3.5 min dough temperature 24°C dough resting time 30 min Afer dividing and moulding pieces of dough of 360 g were obtained. These pieces were proofed during 125 min. The proofed dough pieces were baked: 25 min at 230°C. The specific volume of the bread was 4.65 ml/g. The freshness of the bread was excellent. IV Preparation of a multi-grain bread IV.1 Recipe of the dough 2254 g wheat flour 1272 g dried sour dough 451 g rye meal, coarse 173 g rye fine fraction 1017 g other cereals (p.e. corn, barley) 231 g linseed 231 g soy bean grits 127 g salt 24 g bread improver 116 g yeast 4104 g water 10000 g dough IV.2 The dough was prepared, using a Diosna spirial mixer SP24F. slow speed : 10 min higher speed : 3,5 min dough temperature : 27°C dough resting time: 30 min After dividing and moulding pieces of dough of 900 g were obtained. These pieces were proofed during 60 min. The proofed dough pieces were baked 60 min at 260°C falling down to 210°C. The specific volume of the bread was 2,3 ml/g. The freshness of the bread was excellent. The softness of the crumb was significantly higher than the softness of a bread without rye fine fraction (123 units: 98 units) . After six days the crumb of the above bread showed an improved softness and freshness (50 units: 36 units) .

Claims: CLAIMS 1. Rye-flour, wherein the Rye-flour has a protein content of less than 7 wt%, preferably less than 5 wt%, which flour simultaneously has a reduced dietary fibre content, compared with ordinary Rye-flour and wherein the flour has a particle size distribution such that at least 20 wt% of the particles have a size above 65 μm and more than 94 wt% of the particles have a size of less than 130 μm. 2. Rye-flour, according to claim 1, wherein the dietary fibre content is such that it is reduced with at least 10%, compared with ordinary (natural) Rye-flour. 3. Rye-flour, according to claims 1-2, wherein the α- amylase activity is reduced, preferably with at least 10% compared with ordinary (natural) Rye-flour. 4. Flour blend, suitable for the production of Rye- containing products, wherein ordinary flour is blended with Rye-flour, according to claims 1-3, so that the weight ratio ordinary flour: Rye-flour ranges from (95-5) : (5-95) . 5. Dough for bakery products, comprising the usual ingredients such as flour, salt and water, and optionally yeast, sour inoculum or leavening agents, or other typical ingredients, such as fats, sugar, eggs, gluten or other bread-improvers, wherein the flour applied is the flour of claims 1-3 or the blend of claim 4. 6. Dough for Rye-containing bread, comprising the dough according to claim 5, wherein the water content of the dough is 45-60 wt% (on dough) . 7. Dough for Knacke-brot, comprising the dough according to claim 5, wherein the water content of the dough is 60-70 wt%, while yeast or leavening agent is absent. 8. Fermented sour-dough, comprising at least flour, water and a sour inoculum, wherein the flour at least partly consists of the Rye-flour according to claims 1-3, or the blend of claim 4. 9. Fermented sour dough, comprising the dough according to claim 8, wherein a sour inoculum is applied, while the water content of the dough is at least 25 wt%, preferably 25-32 wt%. 10. Fermented sour dough, wherein the dough according to claim 9 is mixed with enough of a pre-dried flour with a water content of less than 5 wt%, so that the water content, of the mixture is 20-25 wt%. 11. Process for the production of baked Rye-containing products, wherein a dough is produced with the composition according to claims 5-10 in a continuous process, the dough is divided, moulded, fermented (if necessary) and baked. 12. Baked Rye-containing products, obtained after baking of the dough according to claims 5-10. 13. Process for the air classification of a flour, wherein a Rye-flour with 7-12 wt% proteins is milled, so that the milled flour has a particle size distribution such that at least 98% has a size below 130 μm and at least 65 wt% has a size below 32 μm, the milled Rye-flour is subjected to air classification, applying a cut-point of 20-30 and an appropiate air speed, while separating a fine, protein-enriched Rye-flour with more than 12 wt% proteins having a particle size-distribution such that at least 95 wt% has a particle size below 64 μm, while its α-amylase activity is increased with at least 10%, compared with the starting Rye-flour in a yield of 20-40 wt% and a coarse, protein reduced Rye- flour with a protein content of less than 7 wt% having a particle size distribution such that at least 20 wt% has a size above 65 μm and more than 94 wt% has a size of less than 130 μm in a yield of 80-60 wt% 14. Rye-flour, wherein the Rye-flour has a protein content of more than 12 wt%, preferably more than 13 wt%, more preferably more than 15 wt%, which flour simultaneously has 1) an increased dietary fibre content of at least 10% compared with ordinary Rye-flour, 2) a particle size distribution such that at least 95 wt% has a particle size below 64 μm and 3) .rrom which the α-amylase activity is increased with at least 10%, compared with an ordinary Rye-flour. 15. Flour blend, suitable for the production of Rye- containing products, wherein ordinary flour is blended with Rye-flour according to claim 14, so that the weight ratio ordinary flour: Rye-flour ranges from (5- 95) : (95-5) . 16. Flour blend, suitable for the production of French bread, wherein ordinary flour is blended with the Rye- flour according to claim 14, so that the weight ratio ordinary flour:Rye-flour ranges from (99-90) : (1-10) . 17. Dough for bakery products, comprising the usual ingredients such as flour, salt, water, yeast, sour inoculum or leavening agents and optionally other typical ingredients, such as fats, sugar, eggs, gluten or other bread-improvers, wherein the flour applied is the flour of claim 14 or the blend of claims 15 or 16. 18. Baked Rye-containing products, in particular bread and rolls, obtained after baking of the dough according to claim 17.

Inventors: EGLE HANS, KNIEL BAERBEL, WASSERMANN LUDWIG, EGLE, HANS, KNIEL, BAERBEL, WASSERMANN, LUDWIG
Applicants: UNILEVER NV, UNILEVER PLC, UNILEVER N.V.
Application year: 1994
Main classification: A21D2
IPC codes: A21D2, A21D13, A23L1